The present invention relates to the vacuum chambers used for manufacturing. More particularly, the present invention relates to plasma vacuum chambers used for manufacturing.
In the fabrication of semiconductor-based devices (e.g., integrated circuits, or flat panel displays) layers of material may alternately be deposited onto and etched from a substrate surface (e.g., the semiconductor wafer or the glass panel) in a vacuum chamber. To help maintain a constant pressure in the vacuum chamber, a manometer with an elastic diaphragm may be used. Processes in the vacuum chamber may create substances, which may coat the elastic diaphragm, which may change the elastic properties of the diaphragm. A change in the elastic properties of the diaphragm may affect the readings of the manometer.
To facilitate discussion, FIG. 1 is a schematic view of plasma processing chamber 100, which may be used in the prior art. The plasma processing chamber 100 which may be a vacuum chamber that contains a chuck 104, representing the workpiece holder on which a substrate 106 is positioned, plasma generation equipment, which may be an upper electrode 124 and an RF source 126, a gas source 120, and an exhaust port 128. Chuck 104 may be implemented by any suitable chucking technique, e.g., electrostatic, mechanical clamping, vacuum, or the like. A manometer 140 is in fluid connection with the plasma processing chamber 100 through a manometer pipe 142. The manometer pipe 142 allows the pressure in the plasma processing chamber 100 to reach a diaphragm 144 in the manometer 140, so that a change in shape of the manometer diaphragm 144 may be used to measure pressure in the plasma processing chamber 100. A manometer pipe joint 148 allows for a detachable connection between the manometer 140 and the plasma processing chamber 100.
FIG. 2 is an enlarged exploded view of the manometer pipe joint 148, such as a KF fitting used it the prior art. The manometer pipe joint 148, comprises a first pipe end 150, a second pipe e end 152, a centering ring 154, an O-ring 156, a first weld flange 158, a second weld flange 160, and a hinged clamp 170 (only the cross-sectional parts of the hinged clamp is shown for clarity). The first weld flange 158 is welded to the first pipe end 150, as shown. Likewise, the second weld flange 160 is welded to the second pipe end 152. The O-ring 156 is placed to fit around the centering ring 154. The centering ring 154 fits between and within the first weld flange 158 and the second weld flange 160. The centering ring 154 holds the O-ring 156 between a first flange 164 surrounding the first weld flange 158 on the first pipe end 150 and a second flange 166 surrounding the second weld flange 160 on the second pipe end 152. The O-ring 156 is compressed between the first flange 164 and the second flange 166. The hinged clamp 170 presses the first flange 164 and the second flange 166 together so that they compress the O-ring 156. FIG. 3 is a side view of the centering ring 154 within the O-ring 156. A large aperture 304 in the centering of the centering ring 154 allows plasma to pass from the first pipe end 150 to the second pipe end 152.
It is desirable to reduce the coating of substances on the diaphragm.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, a plasma processing device with a manometer with a diaphragm is provided. The plasma processing device has a plasma processing chamber with a passageway, which provides a fluid connection between the plasma processing chamber and the diaphragm. An electrically conductive grid is placed across the cross-section of the passageway.
In addition a method for measuring pressure in a plasma device is provided: Generally, a plasma chamber is provided. A manometer is also provided. A passageway in fluid connection between the plasma chamber and the manometer is also provided. An electrically conductive grid is placed across the passage way.
These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures.